Effect of seed moisture content on seed longevity under ambient storage in senna and muskdana

Abstract

Seed longevity and desiccation sensitivity at different targeted moisture contents under ambient storage conditions were studied in this experiment. Seeds were equilibrated to targeted moisture contents (10%, 7.5% and 5% MC), by the use of silica gel (for drying) and glycerol (for humidification) and sealed in plastic containers with parafilm, followed by storage under ambient temperature (Delhi conditions). A sharp fall in all seed quality attributes (germination percent, seedling length, seedling dry weight and vigour indices) in the other seed moisture regimes (7.5 and 5%) at 10% MC was noticed, while viability was not adversely effected (even after 15 months of storage). But there was no significant difference in germination percentage with respect to moisture regimes (7.5% and 5%), indicating the fact that both are equally good. Other significant finding of this study was both senna and muskdana can with stand low moisture content up to 5%. The results of the study conducted in senna where storability of acid scarified seed was compared with control (un-scarified) had shown that abnormal seedlings and dead seeds percent increased significantly during observation period (3, 6, 9, 12 and 15 months). The experiment clearly established the fact that it is a futile exercise to store scarified seed in senna. This study also confirmed the orthodox seed storage behaviour of the two medicinal plants (Senna and Muskdana) and the capability of seeds to withstand ultra dry storage conditions.